Cleaning solvents or cleaners are used during the manufacture and rework of electronic, telecommunications and other electrical equipment to clean the components prior to final assembly. These cleaners are also used during maintenance operations carried out on electrical equipment in order to provide for proper electrical conductivity where two conductive (e.g., metal) surfaces are to be joined to one another in electrical contact.
Cleaners can be used during the manufacture, maintenance, repair and assembly of printed circuit boards, connectors, relays and contacts, solenoids, motors and motor windings, circuit breakers, circuit breaker panels, transformers, electrical and data communication connectors and switching devices, electronic controls, timers, cable assemblies, splices and terminations, hydraulic and pneumatic equipment, magnetic read/write equipment, optical equipment and the like.
Typically, these cleaners are used to remove contaminants, and more particularly, flux, grease, light oils, corrosive contaminants, oxidation products and the like prior to a final assembly or during or after equipment and component maintenance.
Many such cleaners are provided in aerosol form. Aerosol cleaners typically include a solvent and a propellant. Aerosol formulations can contain constituents that render the formulation relatively flammable. And, the solvents, in and of themselves (e.g., without the propellant) are relatively flammable. This can be problematic in a manufacturing facility during fabrication or in a workplace when performing equipment and component maintenance. In addition, many of these aggressive solvents cannot be used with certain types of plastics due to their aggressive nature. Nevertheless, because of the aggressive cleaning characteristics of these formulations, for many applications their use continues.
One formulation, disclosed in Fitzgerald, U.S. Pat. No. 6,746,998, which is commonly assigned with the present application, discloses a formulation that exhibits lower flammability tendencies and sufficiently aggressive cleaning characteristics. However, greater demands are being made for cleaner formulations that exhibit lower environmental impact, and more specifically, lower global warming potential (GWP).
Accordingly, there exists a need for cleaning compositions having good cleaning characteristics and low flammability. Desirably, such a solvent has a high degree of plastic compatibility and is formulated so that it can be used as a liquid or, with the proper propellant, as an aerosol. More desirably still, such a cleaning solvent formulation has low GWP.